Method and SMF for supporting QOS

Abstract

One disclosure of the present specification provides a method by which a session management function (SMF) supports quality of service (QoS). The method can comprise the steps of: determining, on the basis of a QoS flow not being a guaranteed bit rate (GBR) QoS flow in a multi-access (MA) protocol data unit (PDU) session, that a QoS profile is transmitted to both a third generation partnership project (3GPP) access and a non-3GPP access; determining, on the basis of the QoS flow being the GBR QoS flow in the MA PDU session, that the QoS profile is transmitted to only one of the 3GPP access and the non-3GPP access; and transmitting the QoS profile on the basis of the determinations.

What is claimed is: 
     
       1. A method for supporting a quality of service (QoS), the method performed by a session management function (SMF) node and comprising:
 receiving a request message related to a protocol data unit (PDU) session, 
 wherein the PDU session relates to a multi-access (MA) PDU session over a 3rd generation partnership project (3GPP) access and a non-3GPP access; and 
 transmitting a QoS profile, 
 wherein the QoS profile is transmitted to both of the 3GPP access and the non-3GPP access, based on (i) that the QoS flow is non-guaranteed bit rate (non-GBR) QoS flow, and 
 wherein the QoS profile is transmitted to a first access between the 3GPP access and the non-3GPP access, based on (ii) that the QoS flow is a GBR QoS flow. 
 
     
     
       2. The method of  claim 1 , further comprising:
 determining the first access to transmit the QoS profile, 
 wherein the first access is determined based on (iii) that the first access is being used. 
 
     
     
       3. The method of  claim 1 , further comprising:
 transmitting a QoS rule to a user equipment (UE) based on that the MA PDU session is established. 
 
     
     
       4. The method of  claim 3 , wherein the QoS rule is commonly used for both the 3GPP access and the non-3GPP access. 
     
     
       5. The method of  claim 1 , wherein the MA PDU session is established over both the 3GPP access and the non-3GPP access. 
     
     
       6. The method of  claim 1 , further comprising
 transmitting a steering rule to one or more of a user equipment (UE) and a user plane function (UPF), 
 wherein the steering rule allows the QoS flow to be steered to one or more access among the 3GPP access and the non-3GPP access. 
 
     
     
       7. The method of  claim 1 , further comprising,
 when moving the GBR QoS flow from the first access to a second access among the 3GPP access and the non-3GPP access based on a steering rule, receiving from a UPF information representing that switching is necessary, 
 wherein the received information comprises first information regarding the QoS flow that is a target of switching and second information regarding the second access that is a target access of switching. 
 
     
     
       8. The method of  claim 7 , further comprising
 transmitting, at the SMF, third information informing the UPF of successful completion of the switching of the GBR QoS flow, 
 wherein:
 the QoS profile is transmitted based on the received information, and 
 the third information informing the successful completion of the switching of the GBR QoS flow allows the UPF to perform switching to the second access. 
 
 
     
     
       9. The method of  claim 1 , wherein:
 the first access to which the QoS profile is transmitted is an access currently in use, and 
 the QoS profile is used to set up a resource on the access currently in use. 
 
     
     
       10. A session management function (SMF) for supporting a quality of service (QoS), the SMF comprising:
 a transceiver; and 
 a processor configured to control the transceiver, wherein the processor performs operations of: 
 receiving a request message related to a protocol data unit (PDU) session, 
 wherein the PDU session relates to a multi-access (MA) PDU session over a 3rd generation partnership project (3GPP) access and a non-3GPP access; and transmitting a QoS profile, 
 wherein the QoS profile is transmitted to both of the 3GPP access and the non-3GPP access, based on (i) that the QoS flow is non-guaranteed bit rate (non-GBR) QoS flow, and 
 wherein the QoS profile is transmitted to a first access between the 3GPP access and the non-3GPP access, based on (ii) that the QoS flow is a GBR QoS flow. 
 
     
     
       11. The SMF of  claim 10 , wherein the processor is further configured to perform:
 determining the first access to transmit the QoS profile, 
 wherein the first access is determined based on (iii) that the first access is being used. 
 
     
     
       12. The SMF of  claim 10 , wherein the processor is further configured to perform:
 transmitting a QoS rule to a user equipment (UE) based on that the MA PDU session is established. 
 
     
     
       13. The SMF of  claim 12 , wherein the QoS rule is commonly used for both the 3GPP access and the non-3GPP access. 
     
     
       14. The SMF of  claim 12 , the MA PDU session is established over both the 3GPP access and the non-3GPP access. 
     
     
       15. The SMF of  claim 10 , wherein:
 the processor is further configured to transmit a steering rule to one or more of a user equipment (UE) and a user plane function (UPF), and 
 the steering rule allows the QoS flow to be steered to one or more access among the 3GPP access and the non-3GPP access. 
 
     
     
       16. The SMF of  claim 10 , wherein the processor is further configured to receive, from a UPF through the transceiver, information representing that switching is necessary, when moving the GBR QoS flow from the first access to a second access among the 3GPP access and the non-3GPP access based on a steering rule,
 wherein the received information comprises first information regarding the QoS flow that is a target of switching and second information regarding the second access that is a target access of switching. 
 
     
     
       17. The SMF of  claim 16 , wherein, the processor is further configured to transmit, through the transceiver, third information informing the UPF of successful completion of the switching of the GBR QoS flow,
 wherein: 
 the QoS profile is transmitted based on the received information, and 
 the third information informing the successful completion of the switching of the GBR QoS flow allows the UPF to perform switching to the second access.